This proposal is submitted in response to a need for establishing a resource center in spin trapping for biomedical research. The first step is to apply for a resource-related research project grant within the Biomedical Research Technology Program. Funds are requested for the development of the resource technology, namely spin trapping, over a period of 5 years with the expectation that an application for funds to establish a National Center in this resource technology will be submitted at the end of this period. Specifically, the objective of this proposal is to develop improved methods for the detection, identification and quantitation of free radicals in biological systems with special emphasis on spin trapping techniques involving both ESR and Mass Spectroscopy. New spin traps will be synthesized and new methods of analyzing spin trapping products will be developed. Methods for quantitating spin trapping events will be developed. An extensive hyperfine splitting constant data base will be created and completed for each commonly used spin trap. Access to this data base and/or available information from in-house personnel will be established through electronic communication links. Collaborators will have the immediate benefit of results obtained in this project.